gdb/ui-out.c

   1 /* Output generating routines for GDB.
   2
   3    Copyright (C) 1999-2016 Free Software Foundation, Inc.
   4
   5    Contributed by Cygnus Solutions.
   6    Written by Fernando Nasser for Cygnus.
   7
   8    This file is part of GDB.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  22
  23 #include "defs.h"
  24 #include "expression.h"         /* For language.h */
  25 #include "language.h"
  26 #include "ui-out.h"
  27
  28 #include <vector>
  29 #include <memory>
  30 #include <string>
  31
  32 /* A header of a ui_out_table.  */
  33
  34 class ui_out_hdr
  35 {
  36  public:
  37
  38   explicit ui_out_hdr (int number, int min_width, ui_align alignment,
  39                        const std::string &name, const std::string &header)
  40   : m_number (number),
  41     m_min_width (min_width),
  42     m_alignment (alignment),
  43     m_name (name),
  44     m_header (header)
  45   {
  46   }
  47
  48   int number () const
  49   {
  50     return m_number;
  51   }
  52
  53   int min_width () const
  54   {
  55     return m_min_width;
  56   }
  57
  58   ui_align alignment () const
  59   {
  60     return m_alignment;
  61   }
  62
  63   const std::string &header () const
  64   {
  65     return m_header;
  66   }
  67
  68   const std::string &name () const
  69   {
  70     return m_name;
  71   }
  72
  73  private:
  74
  75   /* The number of the table column this header represents, 1-based.  */
  76   int m_number;
  77
  78   /* Minimal column width in characters.  May or may not be applicable,
  79      depending on the actual implementation of ui_out.  */
  80   int m_min_width;
  81
  82   /* Alignment of the content in the column.  May or may not be applicable,
  83      depending on the actual implementation of ui_out.  */
  84   ui_align m_alignment;
  85
  86   /* Internal column name, used to internally refer to the column.  */
  87   std::string m_name;
  88
  89   /* Printed header text of the column.  */
  90   std::string m_header;
  91 };
  92
  93 /* A level of nesting (either a list or a tuple) in a ui_out output.  */
  94
  95 class ui_out_level
  96 {
  97  public:
  98
  99   explicit ui_out_level (ui_out_type type)
 100   : m_type (type),
 101     m_field_count (0)
 102   {
 103   }
 104
 105   ui_out_type type () const
 106   {
 107     return m_type;
 108   }
 109
 110   int field_count () const
 111   {
 112     return m_field_count;
 113   }
 114
 115   void inc_field_count ()
 116   {
 117     m_field_count++;
 118   }
 119
 120  private:
 121
 122   /* The type of this level.  */
 123   ui_out_type m_type;
 124
 125   /* Count each field; the first element is for non-list fields.  */
 126   int m_field_count;
 127 };
 128
 129
 130 /* Tables are special.  Maintain a separate structure that tracks
 131    their state.  At present an output can only contain a single table
 132    but that restriction might eventually be lifted.  */
 133
 134 struct ui_out_table
 135 {
 136   /* If on, a table is being generated.  */
 137   int flag;
 138
 139   /* If on, the body of a table is being generated.  If off, the table
 140      header is being generated.  */
 141   int body_flag;
 142
 143   /* The level at which each entry of the table is to be found.  A row
 144      (a tuple) is made up of entries.  Consequently ENTRY_LEVEL is one
 145      above that of the table.  */
 146   int entry_level;
 147
 148   /* Number of table columns (as specified in the table_begin call).  */
 149   int columns;
 150
 151   /* String identifying the table (as specified in the table_begin
 152      call).  */
 153   std::string id;
 154
 155   /* Pointers to the column headers.  */
 156   std::vector<std::unique_ptr<ui_out_hdr>> headers;
 157
 158   /* Iterator over the headers vector, used when printing successive fields.  */
 159   std::vector<std::unique_ptr<ui_out_hdr>>::const_iterator headers_iterator;
 160
 161 };
 162
 163
 164 /* The ui_out structure */
 165
 166 struct ui_out
 167   {
 168     int flags;
 169     /* Specific implementation of ui-out.  */
 170     const struct ui_out_impl *impl;
 171     void *data;
 172
 173     /* Current level.  */
 174     int level;
 175
 176     /* Vector to store and track the ui-out levels.  */
 177     std::vector<std::unique_ptr<ui_out_level>> levels;
 178
 179     /* A table, if any.  At present only a single table is supported.  */
 180     struct ui_out_table table;
 181   };
 182
 183 /* The current (inner most) level.  */
 184 static ui_out_level *
 185 current_level (struct ui_out *uiout)
 186 {
 187   return uiout->levels[uiout->level].get ();
 188 }
 189
 190 /* Create a new level, of TYPE.  Return the new level's index.  */
 191 static int
 192 push_level (struct ui_out *uiout,
 193             enum ui_out_type type)
 194 {
 195   std::unique_ptr<ui_out_level> level (new ui_out_level (type));
 196
 197   uiout->levels.push_back (std::move (level));
 198   uiout->level++;
 199
 200   return uiout->level;
 201 }
 202
 203 /* Discard the current level, return the discarded level's index.
 204    TYPE is the type of the level being discarded.  */
 205 static int
 206 pop_level (struct ui_out *uiout,
 207            enum ui_out_type type)
 208 {
 209   /* We had better not underflow the buffer.  */
 210   gdb_assert (uiout->level > 0);
 211   gdb_assert (current_level (uiout)->type () == type);
 212
 213   uiout->levels.pop_back ();
 214   uiout->level--;
 215
 216   return uiout->level + 1;
 217 }
 218
 219 /* These are the interfaces to implementation functions.  */
 220
 221 static void uo_table_begin (struct ui_out *uiout, int nbrofcols,
 222                             int nr_rows, const char *tblid);
 223 static void uo_table_body (struct ui_out *uiout);
 224 static void uo_table_end (struct ui_out *uiout);
 225 static void uo_table_header (struct ui_out *uiout, int width,
 226                              enum ui_align align,
 227                              const std::string &col_name,
 228                              const std::string &col_hdr);
 229 static void uo_begin (struct ui_out *uiout,
 230                       enum ui_out_type type,
 231                       int level, const char *id);
 232 static void uo_end (struct ui_out *uiout,
 233                     enum ui_out_type type,
 234                     int level);
 235 static void uo_field_int (struct ui_out *uiout, int fldno, int width,
 236                           enum ui_align align, const char *fldname, int value);
 237 static void uo_field_skip (struct ui_out *uiout, int fldno, int width,
 238                            enum ui_align align, const char *fldname);
 239 static void uo_field_fmt (struct ui_out *uiout, int fldno, int width,
 240                           enum ui_align align, const char *fldname,
 241                           const char *format, va_list args)
 242      ATTRIBUTE_PRINTF (6, 0);
 243 static void uo_spaces (struct ui_out *uiout, int numspaces);
 244 static void uo_text (struct ui_out *uiout, const char *string);
 245 static void uo_message (struct ui_out *uiout,
 246                         const char *format, va_list args)
 247      ATTRIBUTE_PRINTF (2, 0);
 248 static void uo_wrap_hint (struct ui_out *uiout, const char *identstring);
 249 static void uo_flush (struct ui_out *uiout);
 250 static int uo_redirect (struct ui_out *uiout, struct ui_file *outstream);
 251
 252 /* Prototypes for local functions */
 253
 254 static void append_header_to_list (struct ui_out *uiout, int width,
 255                                    enum ui_align alignment,
 256                                    const std::string &col_name,
 257                                    const std::string &col_hdr);
 258 static int get_next_header (struct ui_out *uiout, int *colno, int *width,
 259                             enum ui_align *alignment, const char **col_hdr);
 260 static void clear_header_list (struct ui_out *uiout);
 261 static void clear_table (struct ui_out *uiout);
 262 static void verify_field (struct ui_out *uiout, int *fldno, int *width,
 263                           enum ui_align *align);
 264
 265 /* exported functions (ui_out API) */
 266
 267 /* Mark beginning of a table.  */
 268
 269 static void
 270 ui_out_table_begin (struct ui_out *uiout, int nbrofcols,
 271                     int nr_rows, const std::string &tblid)
 272 {
 273   if (uiout->table.flag)
 274     internal_error (__FILE__, __LINE__,
 275                     _("tables cannot be nested; table_begin found before \
 276 previous table_end."));
 277
 278   uiout->table.flag = 1;
 279   uiout->table.body_flag = 0;
 280   uiout->table.entry_level = uiout->level + 1;
 281   uiout->table.columns = nbrofcols;
 282   uiout->table.id = tblid;
 283
 284   clear_header_list (uiout);
 285
 286   uo_table_begin (uiout, nbrofcols, nr_rows, uiout->table.id.c_str ());
 287 }
 288
 289 void
 290 ui_out_table_body (struct ui_out *uiout)
 291 {
 292   if (!uiout->table.flag)
 293     internal_error (__FILE__, __LINE__,
 294                     _("table_body outside a table is not valid; it must be \
 295 after a table_begin and before a table_end."));
 296   if (uiout->table.body_flag)
 297     internal_error (__FILE__, __LINE__,
 298                     _("extra table_body call not allowed; there must be \
 299 only one table_body after a table_begin and before a table_end."));
 300   if (uiout->table.headers.size () != uiout->table.columns)
 301     internal_error (__FILE__, __LINE__,
 302                     _("number of headers differ from number of table \
 303 columns."));
 304
 305   uiout->table.body_flag = 1;
 306
 307   uo_table_body (uiout);
 308 }
 309
 310 static void
 311 ui_out_table_end (struct ui_out *uiout)
 312 {
 313   if (!uiout->table.flag)
 314     internal_error (__FILE__, __LINE__,
 315                     _("misplaced table_end or missing table_begin."));
 316
 317   uiout->table.entry_level = 0;
 318   uiout->table.body_flag = 0;
 319   uiout->table.flag = 0;
 320
 321   uo_table_end (uiout);
 322   clear_table (uiout);
 323 }
 324
 325 void
 326 ui_out_table_header (struct ui_out *uiout, int width, enum ui_align alignment,
 327                      const std::string &col_name, const std::string &col_hdr)
 328 {
 329   if (!uiout->table.flag || uiout->table.body_flag)
 330     internal_error (__FILE__, __LINE__,
 331                     _("table header must be specified after table_begin \
 332 and before table_body."));
 333
 334   append_header_to_list (uiout, width, alignment, col_name, col_hdr);
 335
 336   uo_table_header (uiout, width, alignment, col_name, col_hdr);
 337 }
 338
 339 static void
 340 do_cleanup_table_end (void *data)
 341 {
 342   struct ui_out *ui_out = (struct ui_out *) data;
 343
 344   ui_out_table_end (ui_out);
 345 }
 346
 347 struct cleanup *
 348 make_cleanup_ui_out_table_begin_end (struct ui_out *ui_out, int nr_cols,
 349                                      int nr_rows, const char *tblid)
 350 {
 351   ui_out_table_begin (ui_out, nr_cols, nr_rows, tblid);
 352   return make_cleanup (do_cleanup_table_end, ui_out);
 353 }
 354
 355 void
 356 ui_out_begin (struct ui_out *uiout,
 357               enum ui_out_type type,
 358               const char *id)
 359 {
 360   int new_level;
 361
 362   if (uiout->table.flag && !uiout->table.body_flag)
 363     internal_error (__FILE__, __LINE__,
 364                     _("table header or table_body expected; lists must be \
 365 specified after table_body."));
 366
 367   /* Be careful to verify the ``field'' before the new tuple/list is
 368      pushed onto the stack.  That way the containing list/table/row is
 369      verified and not the newly created tuple/list.  This verification
 370      is needed (at least) for the case where a table row entry
 371      contains either a tuple/list.  For that case bookkeeping such as
 372      updating the column count or advancing to the next heading still
 373      needs to be performed.  */
 374   {
 375     int fldno;
 376     int width;
 377     enum ui_align align;
 378
 379     verify_field (uiout, &fldno, &width, &align);
 380   }
 381
 382   new_level = push_level (uiout, type);
 383
 384   /* If the push puts us at the same level as a table row entry, we've
 385      got a new table row.  Put the header pointer back to the start.  */
 386   if (uiout->table.body_flag
 387       && uiout->table.entry_level == new_level)
 388     uiout->table.headers_iterator = uiout->table.headers.begin ();
 389
 390   uo_begin (uiout, type, new_level, id);
 391 }
 392
 393 void
 394 ui_out_end (struct ui_out *uiout,
 395             enum ui_out_type type)
 396 {
 397   int old_level = pop_level (uiout, type);
 398
 399   uo_end (uiout, type, old_level);
 400 }
 401
 402 struct ui_out_end_cleanup_data
 403 {
 404   struct ui_out *uiout;
 405   enum ui_out_type type;
 406 };
 407
 408 static void
 409 do_cleanup_end (void *data)
 410 {
 411   struct ui_out_end_cleanup_data *end_cleanup_data
 412     = (struct ui_out_end_cleanup_data *) data;
 413
 414   ui_out_end (end_cleanup_data->uiout, end_cleanup_data->type);
 415   xfree (end_cleanup_data);
 416 }
 417
 418 static struct cleanup *
 419 make_cleanup_ui_out_end (struct ui_out *uiout,
 420                          enum ui_out_type type)
 421 {
 422   struct ui_out_end_cleanup_data *end_cleanup_data;
 423
 424   end_cleanup_data = XNEW (struct ui_out_end_cleanup_data);
 425   end_cleanup_data->uiout = uiout;
 426   end_cleanup_data->type = type;
 427   return make_cleanup (do_cleanup_end, end_cleanup_data);
 428 }
 429
 430 struct cleanup *
 431 make_cleanup_ui_out_tuple_begin_end (struct ui_out *uiout,
 432                                      const char *id)
 433 {
 434   ui_out_begin (uiout, ui_out_type_tuple, id);
 435   return make_cleanup_ui_out_end (uiout, ui_out_type_tuple);
 436 }
 437
 438 struct cleanup *
 439 make_cleanup_ui_out_list_begin_end (struct ui_out *uiout,
 440                                     const char *id)
 441 {
 442   ui_out_begin (uiout, ui_out_type_list, id);
 443   return make_cleanup_ui_out_end (uiout, ui_out_type_list);
 444 }
 445
 446 void
 447 ui_out_field_int (struct ui_out *uiout,
 448                   const char *fldname,
 449                   int value)
 450 {
 451   int fldno;
 452   int width;
 453   enum ui_align align;
 454
 455   verify_field (uiout, &fldno, &width, &align);
 456
 457   uo_field_int (uiout, fldno, width, align, fldname, value);
 458 }
 459
 460 void
 461 ui_out_field_fmt_int (struct ui_out *uiout,
 462                       int input_width,
 463                       enum ui_align input_align,
 464                       const char *fldname,
 465                       int value)
 466 {
 467   int fldno;
 468   int width;
 469   enum ui_align align;
 470
 471   verify_field (uiout, &fldno, &width, &align);
 472
 473   uo_field_int (uiout, fldno, input_width, input_align, fldname, value);
 474 }
 475
 476 /* Documented in ui-out.h.  */
 477
 478 void
 479 ui_out_field_core_addr (struct ui_out *uiout,
 480                         const char *fldname,
 481                         struct gdbarch *gdbarch,
 482                         CORE_ADDR address)
 483 {
 484   ui_out_field_string (uiout, fldname,
 485                        print_core_address (gdbarch, address));
 486 }
 487
 488 void
 489 ui_out_field_stream (struct ui_out *uiout,
 490                      const char *fldname,
 491                      struct ui_file *stream)
 492 {
 493   std::string buffer = ui_file_as_string (stream);
 494
 495   if (!buffer.empty ())
 496     ui_out_field_string (uiout, fldname, buffer.c_str ());
 497   else
 498     ui_out_field_skip (uiout, fldname);
 499   ui_file_rewind (stream);
 500 }
 501
 502 /* Used to omit a field.  */
 503
 504 void
 505 ui_out_field_skip (struct ui_out *uiout,
 506                    const char *fldname)
 507 {
 508   int fldno;
 509   int width;
 510   enum ui_align align;
 511
 512   verify_field (uiout, &fldno, &width, &align);
 513
 514   uo_field_skip (uiout, fldno, width, align, fldname);
 515 }
 516
 517 void
 518 ui_out_field_string (struct ui_out *uiout,
 519                      const char *fldname,
 520                      const char *string)
 521 {
 522   int fldno;
 523   int width;
 524   enum ui_align align;
 525
 526   verify_field (uiout, &fldno, &width, &align);
 527
 528   uo_field_string (uiout, fldno, width, align, fldname, string);
 529 }
 530
 531 /* VARARGS */
 532 void
 533 ui_out_field_fmt (struct ui_out *uiout,
 534                   const char *fldname,
 535                   const char *format, ...)
 536 {
 537   va_list args;
 538   int fldno;
 539   int width;
 540   enum ui_align align;
 541
 542   /* Will not align, but has to call anyway.  */
 543   verify_field (uiout, &fldno, &width, &align);
 544
 545   va_start (args, format);
 546
 547   uo_field_fmt (uiout, fldno, width, align, fldname, format, args);
 548
 549   va_end (args);
 550 }
 551
 552 void
 553 ui_out_spaces (struct ui_out *uiout, int numspaces)
 554 {
 555   uo_spaces (uiout, numspaces);
 556 }
 557
 558 void
 559 ui_out_text (struct ui_out *uiout,
 560              const char *string)
 561 {
 562   uo_text (uiout, string);
 563 }
 564
 565 void
 566 ui_out_message (struct ui_out *uiout, const char *format, ...)
 567 {
 568   va_list args;
 569
 570   va_start (args, format);
 571   uo_message (uiout, format, args);
 572   va_end (args);
 573 }
 574
 575 void
 576 ui_out_wrap_hint (struct ui_out *uiout, const char *identstring)
 577 {
 578   uo_wrap_hint (uiout, identstring);
 579 }
 580
 581 void
 582 ui_out_flush (struct ui_out *uiout)
 583 {
 584   uo_flush (uiout);
 585 }
 586
 587 int
 588 ui_out_redirect (struct ui_out *uiout, struct ui_file *outstream)
 589 {
 590   return uo_redirect (uiout, outstream);
 591 }
 592
 593 /* Test the flags against the mask given.  */
 594 int
 595 ui_out_test_flags (struct ui_out *uiout, int mask)
 596 {
 597   return (uiout->flags & mask);
 598 }
 599
 600 int
 601 ui_out_is_mi_like_p (struct ui_out *uiout)
 602 {
 603   return uiout->impl->is_mi_like_p;
 604 }
 605
 606 /* Interface to the implementation functions.  */
 607
 608 void
 609 uo_table_begin (struct ui_out *uiout, int nbrofcols,
 610                 int nr_rows,
 611                 const char *tblid)
 612 {
 613   if (!uiout->impl->table_begin)
 614     return;
 615   uiout->impl->table_begin (uiout, nbrofcols, nr_rows, tblid);
 616 }
 617
 618 void
 619 uo_table_body (struct ui_out *uiout)
 620 {
 621   if (!uiout->impl->table_body)
 622     return;
 623   uiout->impl->table_body (uiout);
 624 }
 625
 626 void
 627 uo_table_end (struct ui_out *uiout)
 628 {
 629   if (!uiout->impl->table_end)
 630     return;
 631   uiout->impl->table_end (uiout);
 632 }
 633
 634 void
 635 uo_table_header (struct ui_out *uiout, int width, enum ui_align align,
 636                  const std::string &col_name, const std::string &col_hdr)
 637 {
 638   if (!uiout->impl->table_header)
 639     return;
 640   uiout->impl->table_header (uiout, width, align, col_name, col_hdr);
 641 }
 642
 643 /* Clear the table associated with UIOUT.  */
 644
 645 static void
 646 clear_table (struct ui_out *uiout)
 647 {
 648   uiout->table.id.clear ();
 649   clear_header_list (uiout);
 650 }
 651
 652 void
 653 uo_begin (struct ui_out *uiout,
 654           enum ui_out_type type,
 655           int level,
 656           const char *id)
 657 {
 658   if (uiout->impl->begin == NULL)
 659     return;
 660   uiout->impl->begin (uiout, type, level, id);
 661 }
 662
 663 void
 664 uo_end (struct ui_out *uiout,
 665         enum ui_out_type type,
 666         int level)
 667 {
 668   if (uiout->impl->end == NULL)
 669     return;
 670   uiout->impl->end (uiout, type, level);
 671 }
 672
 673 void
 674 uo_field_int (struct ui_out *uiout, int fldno, int width, enum ui_align align,
 675               const char *fldname,
 676               int value)
 677 {
 678   if (!uiout->impl->field_int)
 679     return;
 680   uiout->impl->field_int (uiout, fldno, width, align, fldname, value);
 681 }
 682
 683 void
 684 uo_field_skip (struct ui_out *uiout, int fldno, int width, enum ui_align align,
 685                const char *fldname)
 686 {
 687   if (!uiout->impl->field_skip)
 688     return;
 689   uiout->impl->field_skip (uiout, fldno, width, align, fldname);
 690 }
 691
 692 void
 693 uo_field_string (struct ui_out *uiout, int fldno, int width,
 694                  enum ui_align align,
 695                  const char *fldname,
 696                  const char *string)
 697 {
 698   if (!uiout->impl->field_string)
 699     return;
 700   uiout->impl->field_string (uiout, fldno, width, align, fldname, string);
 701 }
 702
 703 void
 704 uo_field_fmt (struct ui_out *uiout, int fldno, int width, enum ui_align align,
 705               const char *fldname,
 706               const char *format,
 707               va_list args)
 708 {
 709   if (!uiout->impl->field_fmt)
 710     return;
 711   uiout->impl->field_fmt (uiout, fldno, width, align, fldname, format, args);
 712 }
 713
 714 void
 715 uo_spaces (struct ui_out *uiout, int numspaces)
 716 {
 717   if (!uiout->impl->spaces)
 718     return;
 719   uiout->impl->spaces (uiout, numspaces);
 720 }
 721
 722 void
 723 uo_text (struct ui_out *uiout,
 724          const char *string)
 725 {
 726   if (!uiout->impl->text)
 727     return;
 728   uiout->impl->text (uiout, string);
 729 }
 730
 731 void
 732 uo_message (struct ui_out *uiout,
 733             const char *format,
 734             va_list args)
 735 {
 736   if (!uiout->impl->message)
 737     return;
 738   uiout->impl->message (uiout, format, args);
 739 }
 740
 741 void
 742 uo_wrap_hint (struct ui_out *uiout, const char *identstring)
 743 {
 744   if (!uiout->impl->wrap_hint)
 745     return;
 746   uiout->impl->wrap_hint (uiout, identstring);
 747 }
 748
 749 void
 750 uo_flush (struct ui_out *uiout)
 751 {
 752   if (!uiout->impl->flush)
 753     return;
 754   uiout->impl->flush (uiout);
 755 }
 756
 757 int
 758 uo_redirect (struct ui_out *uiout, struct ui_file *outstream)
 759 {
 760   if (!uiout->impl->redirect)
 761     return -1;
 762   return uiout->impl->redirect (uiout, outstream);
 763 }
 764
 765 /* local functions */
 766
 767 /* List of column headers manipulation routines.  */
 768
 769 static void
 770 clear_header_list (struct ui_out *uiout)
 771 {
 772   uiout->table.headers.clear ();
 773   uiout->table.headers_iterator = uiout->table.headers.end ();
 774 }
 775
 776 static void
 777 append_header_to_list (struct ui_out *uiout,
 778                        int width,
 779                        enum ui_align alignment,
 780                        const std::string &col_name,
 781                        const std::string &col_hdr)
 782 {
 783   std::unique_ptr<ui_out_hdr> temphdr(
 784     new ui_out_hdr (uiout->table.headers.size () + 1, width,
 785                     alignment, col_name, col_hdr));
 786
 787   uiout->table.headers.push_back (std::move (temphdr));
 788 }
 789
 790 /* Extract the format information for the NEXT header and advance
 791    the header pointer.  Return 0 if there was no next header.  */
 792
 793 static int
 794 get_next_header (struct ui_out *uiout,
 795                  int *colno,
 796                  int *width,
 797                  enum ui_align *alignment,
 798                  const char **col_hdr)
 799 {
 800   /* There may be no headers at all or we may have used all columns.  */
 801   if (uiout->table.headers_iterator == uiout->table.headers.end ())
 802     return 0;
 803
 804   ui_out_hdr *hdr = uiout->table.headers_iterator->get ();
 805
 806   *colno = hdr->number ();
 807   *width = hdr->min_width ();
 808   *alignment = hdr->alignment ();
 809   *col_hdr = hdr->header ().c_str ();
 810
 811   /* Advance the header pointer to the next entry.  */
 812   uiout->table.headers_iterator++;
 813
 814   return 1;
 815 }
 816
 817
 818 /* Verify that the field/tuple/list is correctly positioned.  Return
 819    the field number and corresponding alignment (if
 820    available/applicable).  */
 821
 822 static void
 823 verify_field (struct ui_out *uiout, int *fldno, int *width,
 824               enum ui_align *align)
 825 {
 826   ui_out_level *current = current_level (uiout);
 827   const char *text;
 828
 829   if (uiout->table.flag)
 830     {
 831       if (!uiout->table.body_flag)
 832         internal_error (__FILE__, __LINE__,
 833                         _("table_body missing; table fields must be \
 834 specified after table_body and inside a list."));
 835       /* NOTE: cagney/2001-12-08: There was a check here to ensure
 836          that this code was only executed when uiout->level was
 837          greater than zero.  That no longer applies - this code is run
 838          before each table row tuple is started and at that point the
 839          level is zero.  */
 840     }
 841
 842   current->inc_field_count ();
 843
 844   if (uiout->table.body_flag
 845       && uiout->table.entry_level == uiout->level
 846       && get_next_header (uiout, fldno, width, align, &text))
 847     {
 848       if (*fldno != current->field_count ())
 849         internal_error (__FILE__, __LINE__,
 850                         _("ui-out internal error in handling headers."));
 851     }
 852   else
 853     {
 854       *width = 0;
 855       *align = ui_noalign;
 856       *fldno = current->field_count ();
 857     }
 858 }
 859
 860
 861 /* Access to ui-out members data.  */
 862
 863 void *
 864 ui_out_data (struct ui_out *uiout)
 865 {
 866   return uiout->data;
 867 }
 868
 869 /* Access table field parameters.  */
 870 int
 871 ui_out_query_field (struct ui_out *uiout, int colno,
 872                     int *width, int *alignment, const char **col_name)
 873 {
 874   if (!uiout->table.flag)
 875     return 0;
 876
 877   /* Column numbers are 1-based, so convert to 0-based index.  */
 878   int index = colno - 1;
 879
 880   if (index >= 0 && index < uiout->table.headers.size ())
 881     {
 882       ui_out_hdr *hdr = uiout->table.headers[index].get ();
 883
 884       gdb_assert (colno == hdr->number ());
 885
 886       *width = hdr->min_width ();
 887       *alignment = hdr->alignment ();
 888       *col_name = hdr->name ().c_str ();
 889
 890       return 1;
 891     }
 892   else
 893     return 0;
 894 }
 895
 896 /* Initialize private members at startup.  */
 897
 898 struct ui_out *
 899 ui_out_new (const struct ui_out_impl *impl, void *data,
 900             int flags)
 901 {
 902   struct ui_out *uiout = new ui_out ();
 903
 904   uiout->data = data;
 905   uiout->impl = impl;
 906   uiout->flags = flags;
 907   uiout->table.flag = 0;
 908   uiout->table.body_flag = 0;
 909   uiout->level = 0;
 910
 911   /* Create uiout->level 0, the default level.  */
 912   std::unique_ptr<ui_out_level> level (new ui_out_level (ui_out_type_tuple));
 913   uiout->levels.push_back (std::move (level));
 914
 915   uiout->table.headers_iterator = uiout->table.headers.end ();
 916
 917   return uiout;
 918 }